CI: From github action, add label when PR are opened

[benjaminParisel]

CI: From github action, add label when PR are opened

[tbouffard]

❓ I suppose this issue applies only to the bonita-doc repository, which is the only repository that use labels for review workflow. Is that right?

ℹ️ I suggest that when the PR is opened as a Draft, a WIP label is put instead.
The same should be done when switching from In Review to Draft and the opposite

ℹ️ when the PR status change from draft/in-review, put only the 'in review' label if there is no 'review done' or 'ready to merge' label already set

ℹ️ when the PR is mark as approved/rejected, we could also add the "review done" label, remove the "review needed" and add "ready to merge" or "changes requested"

⚠️ the label setting should work for PR created from forks like the one shown in the description (bonitasoft/bonita-doc#2204).
In this case, this is valid to run the workflow on pull_request_target as suggested in https://github.com/actions/labeler#create-workflow

ℹ️ for the list of event that could trigger the GH workflow, see https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#pull_request